Widths of dayside auroral arcs observed at the Chinese Yellow River Station

Due to the altitudinal extent of an auroral arc, its observed width is different at different zenith angles even when its real width is the same. For that reason, former measurements of arc widths were obtained only for arcs located close to the geomagnetic zenith direction. A method to correct arc width is proposed in the paper, which considers the altitudinal extent of auroral arc. Then, we apply this method to the auroral arcs observed at the Chinese Yellow River Station, and analyze the widths of 17,571 dayside auroral arcs. The distributions of the widths are almost the same at different zenith angles with an average width of 18.5 km. Arc widths are narrower as MLT is close to midday.